■ 

0 

, 

~ 

UNITED STATES 

20 

"11 t /i 

ENVIRONMEN' 

WASHINGTON, I 

/N r r`a • v-- 4r.vr 

4*-y 

iv 

,L PROTECTION AGEN Y7 

:. 20460 

~P. At = 

caNr. 

U 

P~ 

SEP 2 0 

MEMORANDUM 

SUBJECT: State Implementation Plai 

Emissions During Malfunct 

FROM: Steven- A. Herma 

'K.

~ 

aA~s-istant Admi ' 

CAssurance 

M C3 

~ is: Policy Regarding EKcesin 

:ions, Startup, and Sh uT.'dowp ( ~

~ -•.. .__- 

~ ° • cn - 

~ or Eo cement and Complipce 

i 

Robert Perciasepe 

Assistant Administrator ] or Air and Radiation 

TO: Regional Administrators, Regions I - X 

EPA's policy for state implemi 

excess emissions during malfunctioi 

maintenance is contained in memorai 

formerly Assistant Administrator f 

dated September 28, 1982 and Februi 

of SIPs'suggests that several conti 

be inconsistent with this policy, o 

inadvertently approved after EPA i: 

because they were part of the SIP i 

been.removed. In order to address 

consistent manner, today we are rei 

1982-83 policy. In so doing, we a: 

clarify several issues of interprel 

that time. The attached updated p 

excess emissions provisions states 

that they can in turn provide grea 

community. 

As EPA stated in its 1982,mem 

emissions ruight aggravate air qual: 

or interfere with maintenance of tl 

standards., EPA views all excess em: 

applicabie emission limitation. Ni 

ntation plans (SIPs) regarding 

s, startup, shutdown, and 

da from Kathleen Bennett, 

r Air, Noise and Radiation .I 

ry 15, 1983. A recent review 

in provisions that.appear to 

ither because they were 

sued the,1982-1983 guidance or 

t that time and have never. 

these provisions in a 

ffirming and supplementing the 

e taking this opportunit.y to, 

ation that have arisen since1 

licy will clarify the types of 

may incorporate into SIPs sof 

er certainty to the regulated 

randum, because excess 

ty so as to prevent attainmeit 

e ambient air quality 

,ssions as violations of the 

!vertheless, EPA recognizes 
- 2 

: that imposition of a penalty for sudden and unavoidable 

malfunctions caused by circumstances entirely beyond the control 

- ~ of- the owner'or operator may not'be`'appropriate. Accordingly, a` 

state or EPA can exercise its "enforcement.discretiori" to refrain 

from taking an enforcement action in these circumstances. 

The main question of interpretation that has arisen 

regarding the old policy is whether a state may go beyond this 

"enforcement discretion" approach and include in its SIP a 

provision that would, in,the context of an enforcement action for 

excess emissions,. excuse a source from penalties if the source 

can demonstrate that it meets certain objective criteria (an 

"affirmative defense"). This policy clarifies that states have 

the discretion to provide'such a defense to actions for.penalties 

brought for excess emissions that arise during certain . 

malfunction, startup, and shutdown episodes, 

In the context of malfunctions, EPA recognizes that even 

equipment that is properly designed and maintained can sometimes 

fail. At the same time, EPA has a fundamental responsibility 

under the Clean Air Act to ensure.that SIPs provide for 

attainment and maintenance of - the national ambient air quality 

•standards ("NAAQS")and protection of PSD increments. Thus, EPA 

cannot approve an affirmative defense provision that would 

undermine the fundamental requirement of attainment and 

maintenance of the NAAQS, or any other.requirement of the Clean 

Air Act: See sections 110(a) and (1) of the Clean Air Act, 92. 

U.S.C. § 7910(a) and (1). 1Accordingly, an acceptable 

affirmative defense provision.may only apply to actions for • 

penalties, but not to antions for injunctive relief. This 

restriction insures that both state and federal authorities 

remain able to'protect air quality standards and PSD increments. 

Furthermore,' this approach is appropriate only when the 

respective cont.ributions of individual sources to pollutant 

concentrations in ambient air are such that:no single source or 

small -group•of•sources has the potential to cause an exceedance 

of th'e NAAQS or-PSD increments. Z Where a sirigle source or small 

1 Pursuant to Section 110(1), EPA'may not approve a SIP 

revision if "the"'revision would interfere with any applicable 

requirement concerning attainment and reasonable further 

progress, or any other applicable requirement of this chapter." 

See also CAA'§ 193, 42 U.S:C. § 7515, and the definitions of 

"emission limitation" and "emission standard" contained in CAA 

§ 302(k), 42, U.S.C. § 7602(k). 

. Z. In the case'of lead and sulfur dioxide, attainment 

problems usually are caused by one or a few sources and an 

~ <S..s ~yF:a? 

r" 
- 3 

group of sources has the potential 

NAAQS or PSD increments, EPA belie , 

apprbath will not be adequate to p: 

environment, and the only appropri+ 

excess,emissions during malfunctioi 

episodes is through an enforcement 

EPA is also taking this oppor 

not intend to approve SIP revision 

director's decision to bar EPA's o 

applicable requirements. Such an 

with the regulatory scheme establi 

Air Act. EPA is also adding conte 

notification criteria to make its 

events consistent with its enforce 

Finally, EPA is clarifying ho 

during periods of startup and shutc 

general, because excess emissions I 

are reasonably foreseeable, they sl 

EPA recognizes that, for some sour 

available emissions control system: 

~ effective during startup or shutdo 

0

respective contributions of indivir _ 4

concentrations in ambient air are : 

small group of sources has the potr 

of the NAAQS or PSD increments, th 

may be addressed in the underlying 

narrowly-tailored SIP revisions thi 

potential impacts on ambient air qi 

of these allowances. In these ins' 

justification of the SIP revision, 

to cause an exceedance of t 

es an affirmative defense 

otect public health and the 

te means of dealing with 

, startup, and shutdown 

discretion approach.' 

unity to clarify that it does 

that would recognize a state 

citizens' ability to enforce 

pproach would be inconsistent 

hed in Tit1e I of the Clean j. 

poraneous record keeping and; 

olicy regarding these types of 

ent approach. 

r excess emissions that occur 

lown should be addressed. In! 

:hat occur during these periods 

iould not be excused. However., 

:e categories,' even the best 

might not be.consistently 

rn periods. In areas where ttie 

lual sources to pollutant 

;uch that no single source or 

mtial to cause an exceedance 

!se technological limitations 

standards themselves th-rough 

t take into account the 

ality caused by the inclusion 

:ances, as part of its 

the state should analyze the 

affirmative defense is not appropr: 

particularly aggravated where a shr 

exceedances or violations are basec 

in place. Although this policy is 

NAAQS, enforcement . discretion is,t] 

for dealing with excess emissions ~ malfunction in a specific area whe: 

group of sources has the potential 

short-term NAAQS. 

~ 

Late. This situation can be ; 

irt-term standard (e.g., where 

i on a few hour period) is also 

generally applicable for other 

ie only appropriate approach-I 

3uring startup, shutdown, and 

:e a single source or a small 

to cause nonattainment of a 

' In'American Trucking Association v. EPA, 175'F. 3d 1027 

~ (D.C. Circ., 1999), the court remanded:the PM2.5 NAAQS to the 

EPA. The Agency has not determined whether this policy is 

appropriate for PM2.5 NAAQS. 
- 4 - 

impact of- the potential worst=case emissions that could occur• 

during startup and shutdown.',." 

, • _. ..... 

In addition to this approach,-states may address this problem 

through the use of enforcement discretion or they may include a 

general affirmative defense provision in their SIPs for short and 

infrequent startup and shutdown periods along the lines outlined 

in the attachment.:- As mentioned above, however; in those areas 

where:a:singLe source or small group of sources has the potential 

to cause•an"jexceedance of the NAAQS or PSD increments, issues 

relating to excess emissions arisi'ng during startup.and shutdown 

may only_•be addressed through an enforcement discretion approach'. 

A11 Regions should review the-SIPs for their•states in light 

of this clarification and take steps to•insure that excess 

emissions provisions in these SIPs are consistent with the 

attached guidance.. 

_ . ; .. • _ 

. 

Attach.ment . . 

° States may account for such emissions by including them in 

their routine rule effectiveness estimates. Rule effectiveness 

estimates may be prepared in accordance with an EPA policy 

document entitled "Guidelines for Estimating and Applying Rule 

Effectiveness for Ozone/Carbon Monoxide State Implementation Plan 

Base Year Inventories." (EPA-452/R-92-010),November-1992. 
Attachment 

POLICY ON EXCESS EMISSIONS DURIIG MALFUNCTIONS, STARTUP, AND 

SHUTDOWN 

Introduction 

This policy specifies when aind'in what manner state ~ implementation plans (SIPs) may provide for defenses to 

viol'ations caused by periods of eiccess emissions due to ~ malfunctions,' startup, or shutdown. Generally, since SIPs must 

provide for attainment and maintenance of the national ambient ! 

air quality standards and the achi ievement of PSD increments, ali 

periods of excess emissions mus't be considered violations. 

Accordingly, any provision that allows for an 'automatic 

exemptionZ for'excess emissions is prohibited. 

However, the imposition of a penalty for.excess emissions 

, during malfunctions caused by circ'umstances entirely beyond the! 

control of the owner or operator may not be appropriate. States 

may, therefore,- as an exercise of their inherent enforcement 

discretion, choose not to penalizela source that has produced 

excess emissions under such circumstances. 

1 

This policy provides an alternative approach to enforcement 

F discretion for areas and pollutants where the respective i 

contributions of individual sources to pollutant concentrationsl 

in ambient air are such that no single source or small group of: 

sources has the potential to causelan exceedance of the NAAQS or 

PSD increments. Where a single source or small group of sources 

has the potential to cause an exceedance of the NAAQS or PSD 

increments, as is often the case for sulfur dioxide and lead,' ' 

EPA believes approaches other thanlenforcement discretion are not 

appropriate. In such cases, any excess emissions may have a 

significant chance of causing an ezceedance or violation of the ~ applicable standard or PSD increment. 

• i 

f .. 

'The termexcess emissionmeans an air emission level which~ exceeds any applicable•emission limitation.Malfunctionmeans a 

sudden and unavoidable breakdown of process or control.equipment. 

z The terrtiautomatic exemotionmeans a generally applicable j 

provision in a SIP that would provide that if certain conditions 

existed during a period of excess emissions, then those 

exceedances would not be considere3 violations. 

'This poli`cy also does not app,ly for purposes of PM2:5 

NAAQS. In American Trucking Association v: EPA, 175 F. 3d 1027 

(D.C. Circ., 1999), the court remanded the PM2.5 NAAQS to the 

EPA. The Agency has not determine3 whether this policy is 

appropriate for PM2.5 NAAQS. 
_ 2 _ 

Except where a single source or small group of sources has 

the potential to cause an exceedance of the NAAQS or PSD 

_-• -increments, states may include in:their-SIPs affirmative 

defenses" for excess emissions, as long as the SIP establishes 

limitations consistent with those set out below. If approved 

into a SIP, an affirmative defense wquld be available to sources 

in an enfor-cement action seeking penalties brought by the state, 

EPA, or citizens: .However, a determination by t_he state not to 

take an enforcement action would not bar EPA or citizen action. s . 

In addition, in certain limited circumstances,•it may be 

appropriate for the state to build into a source-specific,or 

source-category-specific emission standard a provision statingthat the otherwise applicable emission limitations do, not apply 

during narrowly defined startup and shutdown periods. 

.I. AUTOMATIC EXEMPTIONS AND ENFORCEMENT DISCRETION 

If a SI_P contains a . provision addressing excess emissions,. 

it cannot be the type that provides for automatic exemptions. 

Automatic exemptions might aggravate ambient air quality by 

excusing excess•emissions that cause or contribute to a,violation 

of an ambient•air quality standard. Additional grounds for 

disa rovin a SIP that includes the automatic exem tion a roach PP 4• . P PP 

are discussed•in more detail at 42 Fed. Reg. 58171 (November 8, 

1977) and,42-Fed. Reg. 21372 (Apri1.27, 1977). As a,result, EPA 

will not approve any ; SIP revisions that provide automatic 

exemptions.for periods of excess,emissions. 

The best assurance that excess emi_ssions will.not interfere 

with NAAQS attainment, maintenance, or increments is to address 

excess emissions through enforcement discretion. This policy,, ' 

prodides alternative means for addressing excess emissions of 

criteria pollutants. However, • this policy does not apply where a 

single source or small group of sources has the potential to 

cause an exceedance of the NAAQS or PSD increments. Moreover, 

° The"term affirmative defense means, in the.context of an 

enforcement proceeding, a response or defense put forward by a 

defendant,.regarding which the defendant has the burden of proof, 

and the merits of;which are-independently and objectively 

evaluated in a judicial or administrative proceeding. ~ 

S Because all periods of excess emissions are violations and 

because affirmative defense provisions may not apply in actions 

for injunctive-relief, under no circumstances would EPA consider 

periods of excess emissions, even if covered by an affirmative=, 

defense, to be ;'federally permitted releases" under EPCRA or 

CERCLA. 
, 

- 3 

nothing in this guidance should 

~ to include affirmative defense 

be construed 

roiisions in 

as requiring stat 

their SIPs. 

II. AFFIRMATIVE DEFENSES FOR MALFUNCTIONS 

EPA can approve a SIP revisiori that creates an affirmative ~ 

defense to claims for penalties inlenforcement actions regarding 

excess emissions caused by malfunctions as long as the defense 

does not apply to SIP provisions that derive from federally I 

. promulgated performance standards or emission limits, such as new 

source performance standards (NSPS) and national emissions 

standards for hazardous air pollutants (NESHAPS). 6 In addition, 

affirmative defenses are not appropriate for areas and pollutants 

where a single source or small group of sources has the potential 

to cause an exceedance of the NAAQS or PSD increments. 

Furthermore, affirmative defenses to claims for injunctive relief 

are not allowed. To be approved, an affirmative defense 

provision must provide that the defendant has the burden of prolf 

of demonstrating that: I 

1. The excess emissions were caused by a sudden, 

unavoidable breakdown of technology, •beyond the control of the 

owner or operator; 

2. The excess emissions (a) did not stem from any activity 

or event that could have been foreseen and avoided, or planned { 

for, and (b) could not have been avoided by b.etter operation and 

maintenance practices; I 

3. To the maximum extent practicable the air pollution i 

control equipment or processes were maintained and operated in a 

manner consistent with good practice for minimizing emissions; 

4. Repairs were made in an expeditious fashion when the 

operator knew or should have known'that applicable emission 

limitations were being exceeded. Off-shift labor and overtime 

must have been utilized, to the extent practicable, to ensure i 

that such repairs were made as expedit.iously as practicable; 

I 

5. The amount and duration of the excess emissions 

(including any bypass) were minimized to the maximum extent 

practicable during periods of suchlemissions; 

6 To the extent a state includes NSPS or NESHAPS in its SIP, 

the standards should not deviate f rom those that were federally ~

promulgated. Because EPA set these standards taking into account 

technological limitations, additional exemptions would be 

inappropriate. 
y . 

_ 4 _ 

6.° All possible steps were taken to minimize the impact . of 

the excess emissions on ambient air quality; 

7. A11 emission monitoring system_s were kept in operation 

if at all possible; 

8. The owner or.operator's actions in response to the . 

excess emissions_were documented by properly signed,. , 

contemporaneous operating logs, or other relevant evidence; 

9. The-excess emissions were not part of a recurring 

pattern ihdicative of inadequate design, operation, or 

maintenance; and 

10. The owner or operator properly and promptly notified 

the.appropriate regulatory authority.. 

EPA interprets these criteria narrowly. Only those 

malfunctions that are sudden, unavoidable, and unpredictable in 

nature qualify for the defense. For example, a single instance 

of a burst pipe that meets the-above criteria may qualify under 

an affirmative defense. The defense would not be available, 

however, if the facility had a history of similar failures 

because of improper design, improper maintenance, or poor 

operating practices. Furthermore, a source must have taken all 

available measures to compensate for and,resolve the malfunction. 

If a --facility has a baghouse fire that leads to excess emissions, 

the affirmative defense would be appropriate only for the period 

of time necessary to modify or curtail operations to come into 

compliance. The fire should-not be used to excuse excess 

emissions generated during an'extended period of time while the 

operator orders and installs new bags, and relevant SIP language 

must limit applicability of the affirmative defense accordingly. 

III. EXCESS.EMISSIONS DURING STARTUP AND SHUTDOWN 

In general, startup-and.shutdown of proce'ss equipment,are . 

part of the normal operation of a source and should be accounted 

for in the planning, design,- and implementation of operating 

procedures for the process and control equipment. Accordingly, 

it is reasonable to expect,that careful and prudent planning,and 

design will eliminate violations of emission limitations during 

such periods. 

A. SOURCE CATEGORY SPECIFIC RULES -FOR STARTUP AND SHUTDOWN 

For some.source categories, given the types of control 

technologies available, there may exist short periods of : 

emissions during startup and shutdown when, despite best efforts 

regarding planning, design, and operating procedures, the 
- 5 

otherwise applicable emission limitation cannot be met. 

Accordingly, except in the case where a single source or..small 

group of sources has the potentialito"cause'an excdedance'of'th 

NAAQS or PSD increments, it may be,appropriate, in consultation 

with EPA, to create narrowly-tailored SIP revisions that take 

these technological limitations into account and state that the 

otherwise applicable emissions limitations do not apply during 

narrowly defined startup and shutdown periods. To be approved, 

these revisions should meet the foilowing requirements: 

1. The'revision must be limited to specific,.narrowlydefined source categories using specific control strategies 

(e.g., cogeneration facilities burning natural gas and using 

.selective catalytic reduction); " 

2. . Use of.the control strategy for this source category 

must be technically infeasible during startup or shutdown 

periods; 

3. The frequency and duration of operation in startup or 

shutdown mode must be minimized to!the maximum extent 

practicable; i 

t` rY 4. As part of its justification of the SIP revision, the 

state should analyze the potential worst-case emissions that 

could occur during startup and shutdown; 

5. A11 possible steps must be taken to minimize the impac 

of emissions during startup and shutdown on ambient air quality 

6. At all times, the facility must be operated in a manne 

consistent with good practice for minimizing emissions, and.the 

source must have used best efforts regarding planning, design, 

and operating procedures to meet the otherwise applicable 

emission limitation; and r -. 

7. The owner or operator's actions during startup and 

shutdown periods must be documented by properly signed, 

contemporaneous operating logs, orio*_her relevant evidence. 

B. GENERAL AFFIRMATIVE DEFENSE PROVISIONS RELATING TO 

STARTUP AND SHUTDOWN i 

In addition to the approach outlined in Section II(A) abov 

states may address the problem of iexcess emissions occurring 

during startup and shutdown periods through an enforcement 

discretion approach. Further, except in the case where a singl 

source or small group of sources hlas the potential to cause an ~-` exceedance of the NAAQS or PSD increments, states may also adop 

for their SIPs an affirmative defei nse approach. Using this 

~ 
- 6 - 

approach, all pe'riods of excess emissions arising during startup 

and shutdown must be treated as violations,- and the affirmative 

`'defe'n"'se' pro'vision' must not be available for claims 'for injunctive :s 

relief. Furthermore, to be approved, such a provision must 

provide that'the defendant has- ~ the burden of proof of. 

demonstrating that:' 

1. , The periods•of excess einissioins'that occurred during. 

startup andwshutdown were short and infrequent and.could not have 

been prevente.d through careful planning and design; 

2.- The excess emissions were not part of a.recurring 

pattern indicative 4 of- inadequate.design, operation, or 

maintenance; f - 

3: 'Sf the excess emissions•were caused by a bypass (an 

intentional diversion of control•equipment),.then .the bypass was 

unavoidable to prevent loss of life, personal injury, or severe 

property damage; 

4. At all times,' the facility , ivas operated in a manner 

consistent with good practice for minimizing emissions; 

S: The'frequency and duration.of operation in startup or 

shutdown mode was ~ minimized to the maximum extent.practicable; ~4 y 

6. All,possible steps were taken to minimize the impact of 

the excess emissions on ambierit air quality;- 

7. A11 emission monitoring systems were kept in operation 

if at all possible; 

•8. The owner or operator's actions during the p,eriod ofexcess emissions were documented by properly signed, 

contemporaneous operating logs, or other relevant evidence; and 

9. The owner• or operator properly and.promptly notified the 

appropriate regulatory authority. 

If excess emissions occur during routine startup or shutdown 

periods due to a malfunction, then those instances should be 

treated as other malfunctions that are subject to the malfunction 

provisions of this policy. (Reference Part I above).. 

ns~nBesa.+roaAgus,v Y ,sss . . ... ' • ' . - - . 1